Dirty or worn flame sensors, blower motor problems, clogs in the condensate lines, and electrical issues are some of the many problems that can leave your HVAC system failing to deliver the temperatures you've programmed in your thermostat.
Clean the Thermostat
Sometimes, when the room temperature doesn't match the thermostat setting, the problem could be dirt buildup on its interior parts. A dirt coating around the inner components may create excess heat and cause the thermostat to give the wrong readings.
If your thermostat is not reading correctly, it might be due to a dirty or faulty sensor. A quick fix could be to gently clean the sensor with canned air to remove any dust buildup. However, if problems persist, replacing the thermostat could be the next step.
If you're cold even though your thermostat indicates you shouldn't be, your furnace likely isn't the problem. In most cases, it's working just fine. It's your home that needs attention. Lack of insulation, severe air leakage, and/or unbalanced ductwork are frequently to blame.
Uneven heat in your home is typically caused by one or more of three factors: poor airflow in your heating system, inadequate insulation, or air in your home. More specifically, causes include: Restricted airflow between the furnace and vents. Leaky or poorly installed ductwork.
Problems With the HVAC System
If your house is colder than the thermostat setting and you've ruled out thermostat-related issues, it's time to turn your attention to the components of your HVAC system, especially the furnace and heat pump.
Leave both units in place for another 20 minutes, and check the readings again to see if the readings are the same. If the readings between your thermostat and thermometer are still different, you likely have a malfunctioning thermostat and there may be an issue impacting thermostat accuracy and efficiency.
Some of the most common thermostat issues include:
The thermostat is broken, not properly level, or dusty. The thermostat needs to be recalibrated. There is loose wiring causing a thermostat issue.
The calibration screw is typically located in a curved piece of metal. First, remove the control unit from the wall mounting and then locate the screw in the back. Turning it back and forth opens the contacts. Once you feel the setting is correct, turn the calibration screw again to close the contacts.
A bad thermostat can be detected when your AC or furnace is not turning on, your HVAC systems are not turning off, the thermostat not responding, your HVAC system is short-cycling, the room temperature not matching the temperature displayed on the thermostat, and the programmed setting resetting themselves.
One possible reason your AC is not reaching the set temperature is that the thermostat could be dirty. If dirt, dust, or other debris has accumulated within the thermostat box, it can cause the wires to heat up or other issues. Thermostats are cleaned during routine HVAC maintenance to help prevent this from happening.
One of the most common reasons that your thermostat is incorrectly reading your home's temperature is that the temperature sensor is malfunctioning or has failed completely. Replacing a temperature sensor can be very difficult, so there are a few things you should try before you schedule a replacement.
Your HVAC system isn't sized properly
An HVAC system that's too large for your house will cool your home unevenly. It will only cool some rooms off and then shut off versus cooling down the entire house. On the other hand, an HVAC that is too small will have to work above its capacity to cool down a house.
If your thermostat is not reading correctly, it might be due to a dirty or faulty sensor. A quick fix could be to gently clean the sensor with canned air to remove any dust buildup. However, if problems persist, replacing the thermostat could be the next step.
Make sure the breaker is flipped all the way 'off,' then wait for 30-seconds. Turn the breaker back 'on. ' Return to the thermostat control panel and flip the thermostat back into the 'on' position. Finally, set the mode (heat/cool) and the temperature paying careful attention to the flow of conditioned air.
To do so, locate your home's thermostat and tape an accurate thermometer on the wall next to it. Wait 15 minutes and check the temperature reading on both devices. If your readings are three or fewer degrees apart, you should be good to go.
The location of your thermostat plays a role in how well it functions. A thermostat located by an exterior door, a drafty hallway or on an exterior wall will continue to warm the room as it thinks the room is colder than it actually is. Don't let strange or nagging issues impact your peace of mind this winter.
Rooms Are Cold Even With Heating On
This problem often points to inadequate circulation of warm air. It could be due to blocked vents, a failing HVAC fan, or issues with the furnace itself. Ensure that furniture or drapes are not blocking your vents.
Your indoor space will struggle with reaching the set temperature if you're losing conditioned air to the outside. Check your property for drafty windows and doors, and inspect your attic and crawlspace for decayed insulation material.
There may be drafts and pockets of colder air near the floor; The walls are colder and don't emit the usual amount of infrared radiation, so you lose heat due to your body emitting more IR than it receives; You may spend more time indoors and hence have less physical activity, so your body generates less heat.
Adjust the Thermostat
Move your thermostat away from heat-generating appliances and into the center of your home. Your thermostat takes an average temperature reading, so efficient placement is critical. You can also try offsetting your thermostats if you have multiple ones, such as with a 2-degree offset.